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Cruise Carbon Emissions Per Person - Calculate Your Footprint with Our Carbon Calculator
Cruises have been growing in popularity for years, and the industry is expanding rapidly. However, with increasing awareness of climate change, the environmental impact of cruising has come under scrutiny. Cruise ships are often criticized as a particularly climate-damaging form of travel. But how big is their impact really? Our new Cruise Carbon Calculator aims to help answer this question.
The Carbon Footprint of Cruises - Our CO₂ Calculator Explained
Our Cruise Carbon Calculator is built on a broad foundation of scientific studies and is based on the methodology developed by myclimate.org for calculating per capita CO2 emissions from cruises. Factors such as the size and passenger capacity of the cruise ship, trip duration, cabin type (from standard to penthouse), and the number of people per cabin (occupancy rate) are taken into account. The individual inputs are then used to calculate per capita emissions using general data based on the ecoinvent 3.6 database. This database is the world's leading collection of emission data, curated by the renowned ETH Zurich University.
It's important to note that our calculator's result represents per capita emissions in CO₂. However, other pollutants such as methane, nitrogen oxides, and sulfur oxides, which are produced during the operation of a cruise ship, are also proportionally included in this value. This allows for better comparability of values and ensures easier understanding for users. Furthermore, not only are the pollutants from ship propulsion included in the calculation, but also the operation both in port and at sea.
Ship Size is the Main Factor for Per Capita Emissions
The following case study shows how individual factors such as trip duration, cabin type, occupancy rate, and especially ship size affect per capita CO2 emissions:
The Smiths want to go on a cruise again. They look for offers for two people in a standard cabin on different cruise ships. Two offers particularly catch their eye. One with the Viking Sky, a smaller cruise ship with space for about 900 passengers, and another with the new Icons of the Seas from Royal Caribbean, which is one of the largest cruise ships with other 7000 guests. The Smiths want to make their decision based on sustainability this time. Using our CO2 calculator, they determine a per capita CO2 output of 3.11 tons for the potential trip with the Viking Sky. However, when they enter the same data again in the calculator but change the ship size to ">5000 passengers" for the Icon of the Seas, they only come to a CO2 output of 1.24 tons per person. The larger cruise ship is thus at least more climate-friendly in terms of individual guests than the smaller ship with space for fewer passengers.
The main reason for the lower per capita emissions of larger cruise ships lies in their higher space efficiency. The size of a cruise ship and its consumption, especially in terms of fuel, does not increase proportionally to passenger capacity. Although larger ships emit more CO2 in absolute terms than smaller ones, they usually have lower emissions per guest. Of course, larger deviations from this rule can occur depending on the ship.
Ship-Specific Factors and Technologies
For better comparability of the calculation, some simplifications were made. For example, the consumption of the propulsion is calculated as an average across the various propulsion technologies of the ships. However, these can differ greatly in direct comparison. Some older cruise ships still sail the world's oceans powered by heavy fuel oil. The switch to diesel alone saves up to 15% in emissions. Newer ships from Royal Caribbean or the MSC Cruises, are increasingly using LNG (Liquefied Natural Gas), which can reduce CO2 emissions by up to 30%. Cruise lines focusing on smaller ships, such as Hurtigruten, have even presented concept ships like the "Sea Zero," which is set to sail in 2030 with pure electric propulsion through solar and wind energy.
Comparison of Different Fuels
| Fuel | CO2 Reduction Compared to Heavy Fuel Oil | Additional Benefits |
|---|---|---|
| Heavy Fuel Oil | 0% (Reference) | Cost-effective, high energy density |
| Marine Diesel | 5-15% | Lower sulfur emissions |
| LNG | 20-30% | Significantly reduced sulfur and nitrogen oxide emissions |
| Biodiesel | 50-80% | Renewable, but competes with food production |
| Hydrogen | Up to 100% | No direct CO2 emissions, but challenges in production and storage |
| Solar and Wind Energy | Up to 100% | Renewable, emission-free in operation, but limited capacity and weather-dependent |
Measures to Reduce Carbon Footprint
The cruise industry is aware of its responsibility towards the climate and is investing heavily in environmentally friendly technologies and concepts. In addition to new and significantly more efficient propulsion systems, these include:
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Shore Power Supply: In ports, ships can now often be connected to the local power grid to reduce emissions during berthing. The Port of Hamburg has been operating a shore power system since 2016, which can reduce CO2 emissions by up to 2,000 tons per year.
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Route Optimization: More efficient route planning and adjusted speeds can reduce fuel consumption. The cruise line MSC Cruises is already using artificial intelligence to optimize its routes and has been able to reduce fuel consumption by a further 5%.
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Waste Management: Improved systems for waste prevention and disposal. Royal Caribbean has introduced a program called "Save the Waves" aimed at reducing and directly recycling waste on board.
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Carbon Offsetting: Some cruise lines offer passengers the option to offset their carbon footprint by investing in climate protection projects. TUI Cruises (including Mein Schiff) offers the option to offset the carbon footprint of the trip for an additional fee.
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Methanol Propulsion: TUI Cruises' "Mein Schiff 7" set sail in 2024 and is the first cruise ship with methanol propulsion. However, it may take some time before it can be used, as efficient and cost-effective provision of methanol cannot yet be guaranteed everywhere.
The Future of Cruising - It's Getting More Sustainable, but Climate Neutrality is Still a Long Way Off
The cruise industry is increasingly focusing on climate-friendly technologies, and strategies for avoiding CO2 are becoming more holistic. Especially in new builds and the improvement of existing ships, there is an increasing focus on climate neutrality. For leading cruise lines whose concepts are based on large fleets and huge ships, the development towards climate-neutral cruising is a big but necessary challenge. Royal Caribbean, for example, has set itself the goal of offering climate-neutral cruises by 2035. Whether this is a realistic timeframe remains to be seen. Often, retrofitting older ships with sustainable propulsion systems and technologies is very costly and not worthwhile for cruise lines. On the other hand, new builds feature a wide range of technologies that significantly reduce emissions and thus represent a big step towards climate neutrality.
Stricter Regulation Could Help
The EU has now also issued initial regulations aimed at limiting CO2 emissions from cruise ships. In 2023, an agreement was reached between the European Council and Parliament to enact the "FuelEU Maritime" regulation. This aims to reduce greenhouse gas emissions from ships by two percent by 2025, by 14.5 percent by 2035, and by 80 percent by 2050 compared to 2020. The regulations apply to ships with a gross tonnage of over 5,000, which cause 90 percent of CO2 emissions, and affect the energy consumed in or between EU ports as well as partly on voyages outside the EU.
Travelers Can Indeed Make an Impact
Cruise lines and policymakers are already working on a sustainable cruise industry. However, travelers themselves still have the greatest influence. Increased demand for environmentally friendly cruise offerings can further accelerate the development towards climate-neutral cruising. Our CO2 calculator is a first step here to bring transparency to the actual carbon footprint of the planned trip for each individual traveler. This also provides a basis for offsetting one's own emissions by supporting projects to combat climate change. In the case of the Smith family, a donation of just $78 would neutralize the per capita CO2 output. Interesting offers for this can be found in projects like myclimate.
So the next time you want to book a cruise and have found an exciting deal with us, take a look at our CO2 calculator to get a feel for your own carbon footprint.
